Savvy departments learn to survive PACS downtime

PACS outages happen. Surviving the downtime often means retarding the meltdown.

"PACS downtime is a touchy subject," said Sally Grady, director of diagnostic imaging at Florida Hospital in Orlando. "We all like to think it will never happen, but it does. Sometimes it is truly unavoidable."

At Florida Hospital and a growing number of hospitals, PACS is primarily the tool of radiologists, who maintain that no downtime is acceptable, whether scheduled or not.

Vendor contracts typically specify a 98% uptime, but even a 99% uptime equates to outages of about three and a half days a year. While outages can't be avoided entirely, most PACS administrators have devised downtime survival skills to reduce the impact.

"When we know we will take the system down, we try to plan it for times that won't affect the radiologist as much, or pick a time of day when there are enough radiologists present at all campuses to help us catch up once we bring the system back online," Grady said.

At Saint John's Health Center in Santa Monica, CA, PACS administrator Brent Liu has procedures in place to cover either scheduled or unscheduled PACS outages.

"During an unscheduled downtime, our contingency procedures include turning off any automatic archiving functions," Liu said. "All new PACS exams are sent to the desired workstations by the technologists manually instead of automatically, so radiologists can continue to read new cases, although they are aware that they don't have access to older exams for comparison studies."

Liu basically uses the same procedure for scheduled downtimes, but then a list of all scheduled exams can be obtained in advance from the hospital HIS/RIS (hospital/radiology information system). PACS exams are manually prefetched to local workstations so comparison studies are available.

Saint John's has experienced about four days total unscheduled archive server downtime in the past 18 months, due mostly to system disk failures. It ensures against overly lengthy hardware outages by storing hot spare parts on-site, so service personnel do not have to wait for order deliveries. Liu's inventory of hot spares include hard disks and power supplies.

"Most of the downtime delays occur in shipping out a replacement part, so if this can be circumvented by predicting which parts are likely to fail and having them stocked on-site, it dramatically reduces the downtime," Liu said. "It is also a good idea to carry hot spare network switches and devices for the PACS network, since network failures can also cripple a hospital PACS."

Some of the worry of PACS downtime is being addressed by new products coming on the market such as Agfa's PACSWatch 2, which remotely monitors the entire PACS and anticipates problems.